There's lots of information on the SA-2 missle itself, but what about the concrete revetments they were placed in in fixed installations? I have no idea what they look like or how they were designed.

From what I've seen, some SA-2 launchers are simply "plopped down" in the desert (on a level surface behind an earthen revetment), while others are actually placed on concrete pads (again, perhaps behind earthen revetments).

When I built Trumpeter's kit, I imagined a missile placed on a concrete foundation in the desert with blowing sand.

It didn't turn out 100% how I wanted, but I thought it was OK. Someday I may try to make the edge of the circle less apparent and more "buried".

The problem with actually making the whole revetment is that it would be pretty big in 1/35 scale - the ones I saw were a good 50 feet across, made of earth, and shaped like a circle with one end open for an access road (these were mainly desert/Middle-Eastern sites).